A METHOD OF TREATING TEXTILE STRAND MATERIAL IN A JET DYEING APPARATUS AND A JET DYEING APPARATUS FOR CARRYING OUT THE METHOD

Abstract: A method and apparatus for treating textile strand material (7) with gaseous and/or liquid treating formulations in a jet dyeing apparatus, by which method the textile material (7) is placed in a container (1), which is pressure-proof when closed, said material being kept in continuous circulation with the treating formulation in the closed container (1) at least for the duration of the treatment and being advanced by circulation of the air present in the apparatus by means of a blower (4), from which the air under positive pressure impinges the textile material (7) being treated tangentially in forward direction. A constant rate of motion of the textile strand material is maintained by blower (4) being operated by an electric motor (15) and the power consumption thereof being set to a desired constant value.

Description: Title: A method of treating textile strand material in a jet dyeing apparatus and a jet dyeing apparatus for carrying out the method Technical Field The invention relates to a method of the type stated in the preamble to claim 1. Background Art Danish published specification No. 149.640B discloses a method of this type and US patent No. 3,921,420 discloses a jet dyeing apparatus, wherein the textile material is preferably operated by means of air only. However, it is known from the US patent that a cylindrical roller member may co-act to advance the textile material. As the prior art apparatus further are particularly advantageous for dyeing synthetic materials, they are formed as pressure tanks allowing treatment at 130° to 140°C. As stated, the textile material being treated is advanced by means of an air stream produced by a centrifugal blower circulating the air present in the apparatus. The air leaving the blower impinges the textile material under positive pressure tangen- tially in forward direction. This process takes place in a venturi-shaped nozzle. The rate of motion of the fabric depends on the textile material being treated, on the shape of the nozzle and on the effect of the air stream used for advancing of the textiles material. However, the known jet dyeing apparatus are encumbered with the problem that the state of the air changes substantially during a dyeing process. The process is initiated at a low tem erature and atmospheric pressure. The air is then heated, whereby the density of the air decreases and thus also the ability of the air to advance the textile material. As a result, the rate of motion of the textile material decreases. Before the temperature falls below 100°C. the container is closed and the pressure in the container increases to approximately 3 atmospheric pressure at 130°C. This is not caused by externally applied pressure, but due to the fact that the container of the jet dyeing apparatus is pressure-proof when closed, whereby the pressure increases due to the heating. Due to the increased pressure of 3 atm., the density of the air is tripled and the rate of motion of the textile material is increased substantially. In consideration of the dyeing process and in order not to subject the textile material to unnecessary mechanical stress, it is desirable to keep the rate of motion constant or essentially constant. Moreover, a varying rate of motion may be desirable at the different levels of treatment. This has been obtained by means of a swivel damper placed in the circulation or by regulating the velocity of the centrifugal blower. The regulation has been made manually or by means of a regulation system based on a measuring of the rate of motion of the textile material. An accurate measuring of the rate of motion of the textile material is, however, faced with very large practical difficulties. The measuring can be carried out of a idle roller which has to be very smooth-running to render a satisfactorily accurate signal, as there is great risk of the textile material easily sliding in relation to the surface of the roller without the roller rotating with a circumferential velocity corresponding to the one of the textile material. It is next to impossible to the obtain a smooth-running and permanent bearing in the environment within a jet dyeing apparatus. Moreover, the roller is easily blocked by fabric excesses and threads. It is also possible to measure the speed of revolution of the textile material in the dyeing apparatus and thus its rate of motion by detect¬ ing a magnet sown in to the material, whereby a signal is obtained for instance each time the magnet passes the nozzle. This process is more accurate, but in terms of regulation technique, the signal is very poor. Disclosure of the Invention The object of the present invention is to solve the above problem in a simple and accurate manner. The method stated in the introduction is characterised by the characterising part of claim 1. Surprisingly, it has been found that the rate of motion of the textile material may be kept essentially constant, if the power received by the centrifugal blower at the varying temperatures and pressure is kept constant. As a result, the desired rate of motion may be set at the start of the dyeing process and retained throughout the entire process by keeping the power consumption constant. This also implies that a desired varying rate of motion may be obtained by adjusting the power con¬ sumption in a suitable manner during the dyeing process. The invention further relates to an apparatus for carrying out the method. Claims 2, 3, 4 and 5 are directed towards various embodiments of such an apparatus for keeping the power consumption of the motor constant. The most simple adjustment is obtained when a frequency transformer is provided for supplying the driving motor as stated in claim 2. In this embodiment, the frequency and thereby the rate of velocity of the centrifugal blower may be regula- ted so as to keep the power consumption constant at the desired value. However, as stated in claim 3 a hydraulic gear or as stated in claim 4 a variable mechanical gear may be used. Finally, a d.c. motor may be used for operating the blower and a d.c. control may be used for keeping the power at the desired constant level. Brief Description of the Drawings The invention is described in greater detail in the following with reference to the accompanying drawings, in which Fig. 1 is a diagrammatic view of a jet dyeing apparatus for carrying out the inven¬ tion: Fig. 2 shows a block diagram of a first embodiment of the jet dyeing apparatus according to the invention; Fig. 3 shows a block diagram of a second embodiment of the jet dyeing apparatus according to the invention; and Fig. 4 furthermore shows a block diagram of a third embodiment of the jet dyeing apparatus according to the invention. Best Mode for Carrying out the Invention Fig. 1 illustrates a diagrammatic cross-section through a jet dyeing apparatus comprising a container 1 with a filling flap 2. The container may thus be closed in a pressure-proof manner. In the interior of the container, a J-shaped box is arranged extending approximately along two thirds of the periphery of the container 1 essentially at the lower portion thereof. A centrifugal blower 4 is seen centrally (confer Fig. 2) provided with an air inlet 5 extending cylindrically in the axis direction of the container 1 and an outlet opening into a venturi 6. A textile material 7 of great length, for instance several hundred metres, is advanced through the flap 2 and the end portions of the textile material have been sown together so as to form a closed length. As shown, the textile material 7 is advanced through the venturi 6 and extends furthermore into the J-shaped portion 3 of the container 1. Furthermore, a small roller 8 is provided rotating when the textile material passes by for registering the rate of motion thereof. The textile material is advanced in the direction indicated by the arrows in its closed path by means of the centrifugal blower 4, the venturi 6 arranged at the nozzles thereof causing the air to flow tangentially in said direction. At the bottom of the container 1, a treatment liquid 10 is shown, for instance a dye liquid or treatment dye bath, which may be pumped through a heat exchanger 12 by means of a pump 11 outside the container and from there advanced to a number of injection nozzles 13. The treatment bath or dye bath leaving the injection nozzles 13 impinges the textile material 7 spread out in the direction of the axis of the container 1 subsequent to the textile material after having assumed strand shape in the venturi 6. The entire container is filled with a cloud of dye accumulated in the lowermost portion of the container 1, where the dye bath 10 has a surface 14. The tj . bath circuit 10 to 14 has thus been briefly described. As shown, the centrifugal blower 4 is arranged in the interior of the container 1 , while the driving motor thereof is arranged outside the container 1. Fig. 2 is thus a diagrammatic view of an electric motor 15 operating the blower 4 by means of a shaft 16. The motor 15 is supplied with power from a frequency transformer 17 through a cable 18, the frequency transformer naturally being supplied with power from the mains supply, preferably a three-phase connection. The frequency transformer 17 is electrically connected to a comparison means 19 receiving a signal 20 therefrom about the current power consumption. In addition, the comparison means 19 receives a second signal 23 from a connected adjuster, which may be a computer 21 or a manual adjustment, said second signal 23 denot¬ ing the desired set power consumption. The comparison means 19 compares the two signals 20 and 23 with each other and transmits a control signal 24 to the frequency transformer 24 for setting the frequency of power in the cable 18 to the electric motor 15. It should be mentioned that the frequency in the cable 18 for instance may be regulated from 0 to 100 HZ, and that the rotational velocity of the motor 15 and thus the rotational velocity of the blower 4 is essentially proportional to this frequen¬ cy in the cable 18. In the embodiment shown in Fig. 3, a hydraulic gear is arranged between the electric motor 15 and the blower 4, said gear comprising a hydraulic pump 25 with variable displacement operating by the motor 15. The pump 25 is connected to a hydraulic motor 28 with permanent displacement by means of hydraulic wires 26, 27. The hydraulic motor operates the blower 4 by means of the shaft 16. A control unit 29 is connected to the pump 25 and regulates the displacement and thereby the volume current in the hydraulic wires 26,27 between the hydraulic pump 25 and the hydraulic motor 28. As in the embodiment of Fig. 2, the control unit 29 is adjusted either by means of a computer 21 or a manual adjustment 22 to a desired, constant power. The control unit 29 is intended to measure the power of the hydraulic pump 25, compare this with the desired power and to adjust the displacement of the pump so that the difference between the actual measured power and the desired power is nil. It is evident that the displacement of the motor may be regulated instead of that of the pump or that the displacement of both devices may be regulated. In the embodiment shown in Fig. 4, a variable mechanical gear 30 is provided between the electric motor 15 and the blower 4, said gear being provided with a control unit 31 regulating the gear ratio in the mechanical gear in order to keep the power of the electric motor constant at the desired value. In a manner corresponding to the other embodiments in Fig. 2 and Fig. 3, a signal is transmitted to the control unit 31 from a computer or a manual adjustment indicating the desired power. The control unit 31 measures the actual power and compares this with the desired power rendered by the computer or the manual adjustment and the adjusts the gear ratio in the mechanical gear 30 so that the difference between the desired power and the actual power is virtually nil. Even though no embodiment thereof has been shown, the electric motor may be a d.c. motor driving the blower directly. The d.c. motor may correspondingly be provided with a control unit adjusting and maintaining the power at a desired value, being supplied to the control unit from a computer or a manual adjustment. As in the other embodiments of the invention, the control unit measures the actual motor power and thus the actual power and compares this with the desired power. The difference between the desired power and the actual power is subsequently used for setting the rendered power to such a value that said difference practically equals zero. Below, a test result showing the effect obtained by means of the invention is rendered in Table 1. Table 1 Measurement of the circulation time during the dyeing process at constant power consumption of the blower. Absolute Time of circulation Temperamre pressure At power consumption At power consumption °C bar of 40 - 42 Amp of 61 - 63 Amp 40 1.0 4.5 3.6 60 1.0 4.5 3.5 70 1.0 4.3 3.5 80 1.35 4.3 3.5 90 1.50 4.3 3.5 100 1.85 4.4 3.4 110 2.40 4.4 3.4 120 2.75 4.3 3.2 130 3.70 4.6 3.3 The two columns to the right of centre show two different rates of motion of the textile material obtained by setting the current consumption of the motor 15 to 40-42 amperes and 61-63 amperes, respectively and at the same electric voltage the power thus being proportional to the power consumption. The rate of motion of the textile material is measured by measuring its circulating velocity in the dyeing apparatus. It appears from Table 1 that said velocity of motion (circulating velocity) is not very influenced by the temperamre and pressure present in the apparams, but only by the set power (power consumption).

Claims: Claims 1. A method of treating textile strand material (7) with gaseous and/or liquid treating formulation in a jet dyeing apparams, by which method the textile material (7) is placed in a container (1), which is pressure-proof when closed, said material being kept in continuous circulation with the treating formulation in the closed container (1) at least for the duration of the treatment and being advanced by circulation of the air present in the apparams by means of a blower (4), from which the air under positive pressure impinges the textile material (7) tangentially in forward direction, c h a r a c t e r i s e d in that the blower (4) is operated by an electric motor (15), the power consumption thereof being adjusted to a desired constant value. 2. A jet dyeing apparams for carrying out the method according to claim 1 comprising a container (1) pressure-proof in closed position and comprising a blower (4) intended to circulate the air present in the apparams so that the air under positive pressure impinges the textile strand material (7) being treated tangentially in the desired direction and an electric motor (15) intended to operate the blower (4), c h a r a c- 1 e r i s e d in that the electric motor (15) is a frequency controlled motor supplied with power from a frequency transformer (17) which is electrically connected to a comparison means (19) receiving a signal (20) therefrom about the current power consumption and receiving a second signal (23) from a connected adjuster (21,22) about the desired power consumption, having compared the two signals for the frequency transformer (17) said comparison means (19) transmits a control signal (24) for setting the frequency of the power to the electric motor (15). 3. A jet dyeing apparatus for carrying out the method according to claim 1 and of the type stated in the preamble to claim 2, c h a r a c t e r i s e d in that a hydraulic gear is arranged between the electric motor (15) and the blower (4), whereby the electric motor (15) operates a hydraulic pump (25) with variable displacement operating a hydraulic motor (28) with permanent displacement, said motor being interconnected with the blower (4), and that a control unit (29) con- nected to the pump (25) regulates the displacement and thereby the volume current between the hydraulic pump (25) and the hydraulic motor (28). 4. A jet dyeing apparams for carrying out the method according to claim 1 and of the type stated in the preamble to claim 2, characterised in that a variable mechanical gear is arranged between the electric motor (15) and the blower (4), said gear being provided with a control unit (31) adjusting the gear ratio for the keeping the power of the electric motor constant at the desired value. 5. A jet dyeing apparams for carrying out the method according to claim 1 and of the type stated in the preamble to claim 2, characterised in that the electric motor (15) is a d.c. motor provided with d.c. control for maintaining the power at the desired value.

Inventors: HENNINGSEN ERIK, HENNINGSEN, ERIK
Applicants: HENNINGSEN ERIK, HENRIKSEN VALD AS, HENNINGSEN, ERIK, VALD. HENRIKSEN A/S
Application year: 1994
Main classification: D06B3
IPC codes: D06B3